LE BOURGET, France — Air accident investigators recommended Sunday that world aviation bodies draw up new rules requiring medical workers to warn authorities when a pilot's mental health could threaten public safety, after 150 people died when a Germanwings co-pilot deliberately crashed a jet into the French Alps last year.

But the many doctors didn't inform authorities of concerns about his mental health, France's BEA investigation agency said. One doctor referred Lubitz to a psychiatric clinic just two weeks before the crash, it said in its report on the disaster.